Verify fail at reset vektor after adding PLL

Hello and thank you for reply.

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You can use -90 degree clock to SDRAM clock.

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Why -90? I thought it depends on my hardware component. So if I use DE2-115 Board, according to ftp://ftp.altera.com/up/pub/altera_material/11.0/tutorials/vhdl/de2-115/using_the_sdram.pdf page 12, I have to shift the SDRAM clock -3ns with 50MHz.

20ns = 360°

-3ns = 360/20*(-3) = -54°.....

Is that right? I saw -90° in several sources, maybe someone con explain why. I'd appreciate it. Thanks.

Vlad